DB Gates with King County Sheriff's Office said the bag was found and reported by a passenger just before 8 a.m.

Roads in the area were closed for three hours as the KCSO bomb squad worked to clear and secure the scene.

Gates said the fake device was actually made to look like a real pipe bomb. She said some members of the bomb squad on the scene began putting the pieces together and realized the bus they were dealing with was one of the same ones that had been used in the training last week.

However, since they couldn't be 100 percent sure, they had to follow the bomb disposal guidelines to ensure it wasn't an actual bomb.

Gates said it appears they must not have double checked that all the fake devices were off the bus before putting it back in service.

The Obama administration will unveil a major climate change plan Monday aimed at a large reduction in greenhouse gas emissions from the nation's coal-burning power plants, a senior administration official told CNN.